// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2014-2022, NVIDIA CORPORATION.  All rights reserved.
 */

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/mailbox_client.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/phy/phy.h>
#include <linux/phy/tegra/xusb.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

#include <soc/tegra/fuse.h>

#include "xusb.h"

static struct phy *tegra_xusb_pad_of_xlate(struct device *dev,
                                           const struct of_phandle_args *args)
{
        struct tegra_xusb_pad *pad = dev_get_drvdata(dev);
        struct phy *phy = NULL;
        unsigned int i;

        if (args->args_count != 0)
                return ERR_PTR(-EINVAL);

        for (i = 0; i < pad->soc->num_lanes; i++) {
                if (!pad->lanes[i])
                        continue;

                if (pad->lanes[i]->dev.of_node == args->np) {
                        phy = pad->lanes[i];
                        break;
                }
        }

        if (phy == NULL)
                phy = ERR_PTR(-ENODEV);

        return phy;
}

static const struct of_device_id tegra_xusb_padctl_of_match[] = {
#if defined(CONFIG_ARCH_TEGRA_124_SOC) || defined(CONFIG_ARCH_TEGRA_132_SOC)
        {
                .compatible = "nvidia,tegra124-xusb-padctl",
                .data = &tegra124_xusb_padctl_soc,
        },
#endif
#if defined(CONFIG_ARCH_TEGRA_210_SOC)
        {
                .compatible = "nvidia,tegra210-xusb-padctl",
                .data = &tegra210_xusb_padctl_soc,
        },
#endif
#if defined(CONFIG_ARCH_TEGRA_186_SOC)
        {
                .compatible = "nvidia,tegra186-xusb-padctl",
                .data = &tegra186_xusb_padctl_soc,
        },
#endif
#if defined(CONFIG_ARCH_TEGRA_194_SOC)
        {
                .compatible = "nvidia,tegra194-xusb-padctl",
                .data = &tegra194_xusb_padctl_soc,
        },
#endif
#if defined(CONFIG_ARCH_TEGRA_234_SOC)
        {
                .compatible = "nvidia,tegra234-xusb-padctl",
                .data = &tegra234_xusb_padctl_soc,
        },
#endif
        { }
};
MODULE_DEVICE_TABLE(of, tegra_xusb_padctl_of_match);

static struct device_node *
tegra_xusb_find_pad_node(struct tegra_xusb_padctl *padctl, const char *name)
{
        struct device_node *pads, *np;

        pads = of_get_child_by_name(padctl->dev->of_node, "pads");
        if (!pads)
                return NULL;

        np = of_get_child_by_name(pads, name);
        of_node_put(pads);

        return np;
}

static struct device_node *
tegra_xusb_pad_find_phy_node(struct tegra_xusb_pad *pad, unsigned int index)
{
        struct device_node *np, *lanes;

        lanes = of_get_child_by_name(pad->dev.of_node, "lanes");
        if (!lanes)
                return NULL;

        np = of_get_child_by_name(lanes, pad->soc->lanes[index].name);
        of_node_put(lanes);

        return np;
}

int tegra_xusb_lane_parse_dt(struct tegra_xusb_lane *lane,
                             struct device_node *np)
{
        struct device *dev = &lane->pad->dev;
        const char *function;
        int err;

        err = of_property_read_string(np, "nvidia,function", &function);
        if (err < 0)
                return err;

        err = match_string(lane->soc->funcs, lane->soc->num_funcs, function);
        if (err < 0) {
                dev_err(dev, "invalid function \"%s\" for lane \"%pOFn\"\n",
                        function, np);
                return err;
        }

        lane->function = err;

        return 0;
}

static void tegra_xusb_lane_destroy(struct phy *phy)
{
        if (phy) {
                struct tegra_xusb_lane *lane = phy_get_drvdata(phy);

                lane->pad->ops->remove(lane);
                phy_destroy(phy);
        }
}

static void tegra_xusb_pad_release(struct device *dev)
{
        struct tegra_xusb_pad *pad = to_tegra_xusb_pad(dev);

        pad->soc->ops->remove(pad);
}

static const struct device_type tegra_xusb_pad_type = {
        .release = tegra_xusb_pad_release,
};

int tegra_xusb_pad_init(struct tegra_xusb_pad *pad,
                        struct tegra_xusb_padctl *padctl,
                        struct device_node *np)
{
        int err;

        device_initialize(&pad->dev);
        INIT_LIST_HEAD(&pad->list);
        pad->dev.parent = padctl->dev;
        pad->dev.type = &tegra_xusb_pad_type;
        pad->dev.of_node = np;
        pad->padctl = padctl;

        err = dev_set_name(&pad->dev, "%s", pad->soc->name);
        if (err < 0)
                goto unregister;

        err = device_add(&pad->dev);
        if (err < 0)
                goto unregister;

        return 0;

unregister:
        device_unregister(&pad->dev);
        return err;
}

int tegra_xusb_pad_register(struct tegra_xusb_pad *pad,
                            const struct phy_ops *ops)
{
        struct device_node *children;
        struct phy *lane;
        unsigned int i;
        int err;

        children = of_get_child_by_name(pad->dev.of_node, "lanes");
        if (!children)
                return -ENODEV;

        pad->lanes = devm_kcalloc(&pad->dev, pad->soc->num_lanes, sizeof(lane),
                                  GFP_KERNEL);
        if (!pad->lanes) {
                of_node_put(children);
                return -ENOMEM;
        }

        for (i = 0; i < pad->soc->num_lanes; i++) {
                struct device_node *np = tegra_xusb_pad_find_phy_node(pad, i);
                struct tegra_xusb_lane *lane;

                /* skip disabled lanes */
                if (!np || !of_device_is_available(np)) {
                        of_node_put(np);
                        continue;
                }

                pad->lanes[i] = phy_create(&pad->dev, np, ops);
                if (IS_ERR(pad->lanes[i])) {
                        err = PTR_ERR(pad->lanes[i]);
                        of_node_put(np);
                        goto remove;
                }

                lane = pad->ops->probe(pad, np, i);
                if (IS_ERR(lane)) {
                        phy_destroy(pad->lanes[i]);
                        err = PTR_ERR(lane);
                        goto remove;
                }

                list_add_tail(&lane->list, &pad->padctl->lanes);
                phy_set_drvdata(pad->lanes[i], lane);
        }

        pad->provider = of_phy_provider_register_full(&pad->dev, children,
                                                      tegra_xusb_pad_of_xlate);
        if (IS_ERR(pad->provider)) {
                err = PTR_ERR(pad->provider);
                goto remove;
        }

        return 0;

remove:
        while (i--)
                tegra_xusb_lane_destroy(pad->lanes[i]);

        of_node_put(children);

        return err;
}

void tegra_xusb_pad_unregister(struct tegra_xusb_pad *pad)
{
        unsigned int i = pad->soc->num_lanes;

        of_phy_provider_unregister(pad->provider);

        while (i--)
                tegra_xusb_lane_destroy(pad->lanes[i]);

        device_unregister(&pad->dev);
}

static struct tegra_xusb_pad *
tegra_xusb_pad_create(struct tegra_xusb_padctl *padctl,
                      const struct tegra_xusb_pad_soc *soc)
{
        struct tegra_xusb_pad *pad;
        struct device_node *np;
        int err;

        np = tegra_xusb_find_pad_node(padctl, soc->name);
        if (!np || !of_device_is_available(np))
                return NULL;

        pad = soc->ops->probe(padctl, soc, np);
        if (IS_ERR(pad)) {
                err = PTR_ERR(pad);
                dev_err(padctl->dev, "failed to create pad %s: %d\n",
                        soc->name, err);
                return ERR_PTR(err);
        }

        /* XXX move this into ->probe() to avoid string comparison */
        if (strcmp(soc->name, "pcie") == 0)
                padctl->pcie = pad;

        if (strcmp(soc->name, "sata") == 0)
                padctl->sata = pad;

        if (strcmp(soc->name, "usb2") == 0)
                padctl->usb2 = pad;

        if (strcmp(soc->name, "ulpi") == 0)
                padctl->ulpi = pad;

        if (strcmp(soc->name, "hsic") == 0)
                padctl->hsic = pad;

        return pad;
}

static void __tegra_xusb_remove_pads(struct tegra_xusb_padctl *padctl)
{
        struct tegra_xusb_pad *pad, *tmp;

        list_for_each_entry_safe_reverse(pad, tmp, &padctl->pads, list) {
                list_del(&pad->list);
                tegra_xusb_pad_unregister(pad);
        }
}

static void tegra_xusb_remove_pads(struct tegra_xusb_padctl *padctl)
{
        mutex_lock(&padctl->lock);
        __tegra_xusb_remove_pads(padctl);
        mutex_unlock(&padctl->lock);
}

static void tegra_xusb_lane_program(struct tegra_xusb_lane *lane)
{
        struct tegra_xusb_padctl *padctl = lane->pad->padctl;
        const struct tegra_xusb_lane_soc *soc = lane->soc;
        u32 value;

        /* skip single function lanes */
        if (soc->num_funcs < 2)
                return;

        if (lane->pad->ops->iddq_enable)
                lane->pad->ops->iddq_enable(lane);

        /* choose function */
        value = padctl_readl(padctl, soc->offset);
        value &= ~(soc->mask << soc->shift);
        value |= lane->function << soc->shift;
        padctl_writel(padctl, value, soc->offset);

        if (lane->pad->ops->iddq_disable)
                lane->pad->ops->iddq_disable(lane);
}

static void tegra_xusb_pad_program(struct tegra_xusb_pad *pad)
{
        unsigned int i;

        for (i = 0; i < pad->soc->num_lanes; i++) {
                struct tegra_xusb_lane *lane;

                if (pad->lanes[i]) {
                        lane = phy_get_drvdata(pad->lanes[i]);
                        tegra_xusb_lane_program(lane);
                }
        }
}

static int tegra_xusb_setup_pads(struct tegra_xusb_padctl *padctl)
{
        struct tegra_xusb_pad *pad;
        unsigned int i;

        mutex_lock(&padctl->lock);

        for (i = 0; i < padctl->soc->num_pads; i++) {
                const struct tegra_xusb_pad_soc *soc = padctl->soc->pads[i];
                int err;

                pad = tegra_xusb_pad_create(padctl, soc);
                if (IS_ERR(pad)) {
                        err = PTR_ERR(pad);
                        dev_err(padctl->dev, "failed to create pad %s: %d\n",
                                soc->name, err);
                        __tegra_xusb_remove_pads(padctl);
                        mutex_unlock(&padctl->lock);
                        return err;
                }

                if (!pad)
                        continue;

                list_add_tail(&pad->list, &padctl->pads);
        }

        list_for_each_entry(pad, &padctl->pads, list)
                tegra_xusb_pad_program(pad);

        mutex_unlock(&padctl->lock);
        return 0;
}

bool tegra_xusb_lane_check(struct tegra_xusb_lane *lane,
                                  const char *function)
{
        const char *func = lane->soc->funcs[lane->function];

        return strcmp(function, func) == 0;
}

struct tegra_xusb_lane *tegra_xusb_find_lane(struct tegra_xusb_padctl *padctl,
                                             const char *type,
                                             unsigned int index)
{
        struct tegra_xusb_lane *lane, *hit = ERR_PTR(-ENODEV);
        char *name;

        name = kasprintf(GFP_KERNEL, "%s-%u", type, index);
        if (!name)
                return ERR_PTR(-ENOMEM);

        list_for_each_entry(lane, &padctl->lanes, list) {
                if (strcmp(lane->soc->name, name) == 0) {
                        hit = lane;
                        break;
                }
        }

        kfree(name);
        return hit;
}

struct tegra_xusb_lane *
tegra_xusb_port_find_lane(struct tegra_xusb_port *port,
                          const struct tegra_xusb_lane_map *map,
                          const char *function)
{
        struct tegra_xusb_lane *lane, *match = ERR_PTR(-ENODEV);

        for (; map->type; map++) {
                if (port->index != map->port)
                        continue;

                lane = tegra_xusb_find_lane(port->padctl, map->type,
                                            map->index);
                if (IS_ERR(lane))
                        continue;

                if (!tegra_xusb_lane_check(lane, function))
                        continue;

                if (!IS_ERR(match))
                        dev_err(&port->dev, "conflicting match: %s-%u / %s\n",
                                map->type, map->index, match->soc->name);
                else
                        match = lane;
        }

        return match;
}

static struct device_node *
tegra_xusb_find_port_node(struct tegra_xusb_padctl *padctl, const char *type,
                          unsigned int index)
{
        struct device_node *ports, *np;
        char *name;

        ports = of_get_child_by_name(padctl->dev->of_node, "ports");
        if (!ports)
                return NULL;

        name = kasprintf(GFP_KERNEL, "%s-%u", type, index);
        if (!name) {
                of_node_put(ports);
                return NULL;
        }
        np = of_get_child_by_name(ports, name);
        kfree(name);
        of_node_put(ports);

        return np;
}

struct tegra_xusb_port *
tegra_xusb_find_port(struct tegra_xusb_padctl *padctl, const char *type,
                     unsigned int index)
{
        struct tegra_xusb_port *port;
        struct device_node *np;

        np = tegra_xusb_find_port_node(padctl, type, index);
        if (!np)
                return NULL;

        list_for_each_entry(port, &padctl->ports, list) {
                if (np == port->dev.of_node) {
                        of_node_put(np);
                        return port;
                }
        }

        of_node_put(np);

        return NULL;
}

struct tegra_xusb_usb2_port *
tegra_xusb_find_usb2_port(struct tegra_xusb_padctl *padctl, unsigned int index)
{
        struct tegra_xusb_port *port;

        port = tegra_xusb_find_port(padctl, "usb2", index);
        if (port)
                return to_usb2_port(port);

        return NULL;
}

struct tegra_xusb_usb3_port *
tegra_xusb_find_usb3_port(struct tegra_xusb_padctl *padctl, unsigned int index)
{
        struct tegra_xusb_port *port;

        port = tegra_xusb_find_port(padctl, "usb3", index);
        if (port)
                return to_usb3_port(port);

        return NULL;
}

static void tegra_xusb_port_release(struct device *dev)
{
        struct tegra_xusb_port *port = to_tegra_xusb_port(dev);

        if (port->ops->release)
                port->ops->release(port);
}

static const struct device_type tegra_xusb_port_type = {
        .release = tegra_xusb_port_release,
};

static int tegra_xusb_port_init(struct tegra_xusb_port *port,
                                struct tegra_xusb_padctl *padctl,
                                struct device_node *np,
                                const char *name,
                                unsigned int index)
{
        int err;

        INIT_LIST_HEAD(&port->list);
        port->padctl = padctl;
        port->index = index;

        device_initialize(&port->dev);
        port->dev.type = &tegra_xusb_port_type;
        device_set_node(&port->dev, of_fwnode_handle(of_node_get(np)));
        port->dev.parent = padctl->dev;

        err = dev_set_name(&port->dev, "%s-%u", name, index);
        if (err < 0)
                goto put_device;

        err = device_add(&port->dev);
        if (err < 0)
                goto put_device;

        return 0;

put_device:
        put_device(&port->dev);
        return err;
}

static void tegra_xusb_port_unregister(struct tegra_xusb_port *port)
{
        if (!IS_ERR_OR_NULL(port->usb_role_sw)) {
                of_platform_depopulate(&port->dev);
                usb_role_switch_unregister(port->usb_role_sw);
                cancel_work_sync(&port->usb_phy_work);
                usb_remove_phy(&port->usb_phy);
                port->usb_phy.dev->driver = NULL;
        }

        if (port->ops->remove)
                port->ops->remove(port);

        device_unregister(&port->dev);
}

static const char *const modes[] = {
        [USB_DR_MODE_UNKNOWN] = "",
        [USB_DR_MODE_HOST] = "host",
        [USB_DR_MODE_PERIPHERAL] = "peripheral",
        [USB_DR_MODE_OTG] = "otg",
};

static const char * const usb_roles[] = {
        [USB_ROLE_NONE]         = "none",
        [USB_ROLE_HOST]         = "host",
        [USB_ROLE_DEVICE]       = "device",
};

static enum usb_phy_events to_usb_phy_event(enum usb_role role)
{
        switch (role) {
        case USB_ROLE_DEVICE:
                return USB_EVENT_VBUS;

        case USB_ROLE_HOST:
                return USB_EVENT_ID;

        default:
                return USB_EVENT_NONE;
        }
}

static void tegra_xusb_usb_phy_work(struct work_struct *work)
{
        struct tegra_xusb_port *port = container_of(work,
                                                    struct tegra_xusb_port,
                                                    usb_phy_work);
        enum usb_role role = usb_role_switch_get_role(port->usb_role_sw);

        usb_phy_set_event(&port->usb_phy, to_usb_phy_event(role));

        dev_dbg(&port->dev, "%s(): calling notifier for role %s\n", __func__,
                usb_roles[role]);

        atomic_notifier_call_chain(&port->usb_phy.notifier, 0, &port->usb_phy);
}

static int tegra_xusb_role_sw_set(struct usb_role_switch *sw,
                                  enum usb_role role)
{
        struct tegra_xusb_port *port = usb_role_switch_get_drvdata(sw);

        dev_dbg(&port->dev, "%s(): role %s\n", __func__, usb_roles[role]);

        schedule_work(&port->usb_phy_work);

        return 0;
}

static int tegra_xusb_set_peripheral(struct usb_otg *otg,
                                     struct usb_gadget *gadget)
{
        struct tegra_xusb_port *port = container_of(otg->usb_phy,
                                                    struct tegra_xusb_port,
                                                    usb_phy);

        if (gadget != NULL)
                schedule_work(&port->usb_phy_work);

        return 0;
}

static int tegra_xusb_set_host(struct usb_otg *otg, struct usb_bus *host)
{
        struct tegra_xusb_port *port = container_of(otg->usb_phy,
                                                    struct tegra_xusb_port,
                                                    usb_phy);

        if (host != NULL)
                schedule_work(&port->usb_phy_work);

        return 0;
}


static int tegra_xusb_setup_usb_role_switch(struct tegra_xusb_port *port)
{
        struct tegra_xusb_lane *lane;
        struct usb_role_switch_desc role_sx_desc = {
                .fwnode = dev_fwnode(&port->dev),
                .set = tegra_xusb_role_sw_set,
                .allow_userspace_control = true,
        };
        int err = 0;

        /*
         * USB role switch driver needs parent driver owner info. This is a
         * suboptimal solution. TODO: Need to revisit this in a follow-up patch
         * where an optimal solution is possible with changes to USB role
         * switch driver.
         */
        port->dev.driver = devm_kzalloc(&port->dev,
                                        sizeof(struct device_driver),
                                        GFP_KERNEL);
        if (!port->dev.driver)
                return -ENOMEM;

        port->dev.driver->owner  = THIS_MODULE;

        port->usb_role_sw = usb_role_switch_register(&port->dev,
                                                     &role_sx_desc);
        if (IS_ERR(port->usb_role_sw)) {
                err = PTR_ERR(port->usb_role_sw);
                dev_err(&port->dev, "failed to register USB role switch: %d",
                        err);
                return err;
        }

        INIT_WORK(&port->usb_phy_work, tegra_xusb_usb_phy_work);
        usb_role_switch_set_drvdata(port->usb_role_sw, port);

        port->usb_phy.otg = devm_kzalloc(&port->dev, sizeof(struct usb_otg),
                                         GFP_KERNEL);
        if (!port->usb_phy.otg)
                return -ENOMEM;

        lane = tegra_xusb_find_lane(port->padctl, "usb2", port->index);
        if (IS_ERR(lane))
                return PTR_ERR(lane);

        /*
         * Assign phy dev to usb-phy dev. Host/device drivers can use phy
         * reference to retrieve usb-phy details.
         */
        port->usb_phy.dev = &lane->pad->lanes[port->index]->dev;
        port->usb_phy.dev->driver = port->dev.driver;
        port->usb_phy.otg->usb_phy = &port->usb_phy;
        port->usb_phy.otg->set_peripheral = tegra_xusb_set_peripheral;
        port->usb_phy.otg->set_host = tegra_xusb_set_host;

        err = usb_add_phy_dev(&port->usb_phy);
        if (err < 0) {
                dev_err(&port->dev, "Failed to add USB PHY: %d\n", err);
                return err;
        }

        /* populate connector entry */
        of_platform_populate(port->dev.of_node, NULL, NULL, &port->dev);

        return err;
}

static void tegra_xusb_parse_usb_role_default_mode(struct tegra_xusb_port *port)
{
        enum usb_role role = USB_ROLE_NONE;
        enum usb_dr_mode mode = usb_get_role_switch_default_mode(&port->dev);

        if (mode == USB_DR_MODE_HOST)
                role = USB_ROLE_HOST;
        else if (mode == USB_DR_MODE_PERIPHERAL)
                role = USB_ROLE_DEVICE;

        if (role != USB_ROLE_NONE) {
                usb_role_switch_set_role(port->usb_role_sw, role);
                dev_dbg(&port->dev, "usb role default mode is %s", modes[mode]);
        }
}

static int tegra_xusb_usb2_port_parse_dt(struct tegra_xusb_usb2_port *usb2)
{
        struct tegra_xusb_port *port = &usb2->base;
        struct device_node *np = port->dev.of_node;
        const char *mode;
        int err;

        usb2->internal = of_property_read_bool(np, "nvidia,internal");

        if (!of_property_read_string(np, "mode", &mode)) {
                int err = match_string(modes, ARRAY_SIZE(modes), mode);
                if (err < 0) {
                        dev_err(&port->dev, "invalid value %s for \"mode\"\n",
                                mode);
                        usb2->mode = USB_DR_MODE_UNKNOWN;
                } else {
                        usb2->mode = err;
                }
        } else {
                usb2->mode = USB_DR_MODE_HOST;
        }

        /* usb-role-switch property is mandatory for OTG/Peripheral modes */
        if (usb2->mode == USB_DR_MODE_PERIPHERAL ||
            usb2->mode == USB_DR_MODE_OTG) {
                if (of_property_read_bool(np, "usb-role-switch")) {
                        err = tegra_xusb_setup_usb_role_switch(port);
                        if (err < 0)
                                return err;
                        tegra_xusb_parse_usb_role_default_mode(port);
                } else {
                        dev_err(&port->dev, "usb-role-switch not found for %s mode",
                                modes[usb2->mode]);
                        return -EINVAL;
                }
        }

        usb2->supply = regulator_get(&port->dev, "vbus");
        return PTR_ERR_OR_ZERO(usb2->supply);
}

static int tegra_xusb_add_usb2_port(struct tegra_xusb_padctl *padctl,
                                    unsigned int index)
{
        struct tegra_xusb_usb2_port *usb2;
        struct device_node *np;
        int err = 0;

        /*
         * USB2 ports don't require additional properties, but if the port is
         * marked as disabled there is no reason to register it.
         */
        np = tegra_xusb_find_port_node(padctl, "usb2", index);
        if (!np || !of_device_is_available(np))
                goto out;

        usb2 = kzalloc_obj(*usb2);
        if (!usb2) {
                err = -ENOMEM;
                goto out;
        }

        err = tegra_xusb_port_init(&usb2->base, padctl, np, "usb2", index);
        if (err < 0)
                goto out;

        usb2->base.ops = padctl->soc->ports.usb2.ops;

        usb2->base.lane = usb2->base.ops->map(&usb2->base);
        if (IS_ERR(usb2->base.lane)) {
                err = PTR_ERR(usb2->base.lane);
                tegra_xusb_port_unregister(&usb2->base);
                goto out;
        }

        err = tegra_xusb_usb2_port_parse_dt(usb2);
        if (err < 0) {
                tegra_xusb_port_unregister(&usb2->base);
                goto out;
        }

        list_add_tail(&usb2->base.list, &padctl->ports);

out:
        of_node_put(np);
        return err;
}

void tegra_xusb_usb2_port_release(struct tegra_xusb_port *port)
{
        struct tegra_xusb_usb2_port *usb2 = to_usb2_port(port);

        kfree(usb2);
}

void tegra_xusb_usb2_port_remove(struct tegra_xusb_port *port)
{
        struct tegra_xusb_usb2_port *usb2 = to_usb2_port(port);

        regulator_put(usb2->supply);
}

static int tegra_xusb_ulpi_port_parse_dt(struct tegra_xusb_ulpi_port *ulpi)
{
        struct tegra_xusb_port *port = &ulpi->base;
        struct device_node *np = port->dev.of_node;

        ulpi->internal = of_property_read_bool(np, "nvidia,internal");

        return 0;
}

static int tegra_xusb_add_ulpi_port(struct tegra_xusb_padctl *padctl,
                                    unsigned int index)
{
        struct tegra_xusb_ulpi_port *ulpi;
        struct device_node *np;
        int err = 0;

        np = tegra_xusb_find_port_node(padctl, "ulpi", index);
        if (!np || !of_device_is_available(np))
                goto out;

        ulpi = kzalloc_obj(*ulpi);
        if (!ulpi) {
                err = -ENOMEM;
                goto out;
        }

        err = tegra_xusb_port_init(&ulpi->base, padctl, np, "ulpi", index);
        if (err < 0)
                goto out;

        ulpi->base.ops = padctl->soc->ports.ulpi.ops;

        ulpi->base.lane = ulpi->base.ops->map(&ulpi->base);
        if (IS_ERR(ulpi->base.lane)) {
                err = PTR_ERR(ulpi->base.lane);
                tegra_xusb_port_unregister(&ulpi->base);
                goto out;
        }

        err = tegra_xusb_ulpi_port_parse_dt(ulpi);
        if (err < 0) {
                tegra_xusb_port_unregister(&ulpi->base);
                goto out;
        }

        list_add_tail(&ulpi->base.list, &padctl->ports);

out:
        of_node_put(np);
        return err;
}

void tegra_xusb_ulpi_port_release(struct tegra_xusb_port *port)
{
        struct tegra_xusb_ulpi_port *ulpi = to_ulpi_port(port);

        kfree(ulpi);
}

static int tegra_xusb_hsic_port_parse_dt(struct tegra_xusb_hsic_port *hsic)
{
        /* XXX */
        return 0;
}

static int tegra_xusb_add_hsic_port(struct tegra_xusb_padctl *padctl,
                                    unsigned int index)
{
        struct tegra_xusb_hsic_port *hsic;
        struct device_node *np;
        int err = 0;

        np = tegra_xusb_find_port_node(padctl, "hsic", index);
        if (!np || !of_device_is_available(np))
                goto out;

        hsic = kzalloc_obj(*hsic);
        if (!hsic) {
                err = -ENOMEM;
                goto out;
        }

        err = tegra_xusb_port_init(&hsic->base, padctl, np, "hsic", index);
        if (err < 0)
                goto out;

        hsic->base.ops = padctl->soc->ports.hsic.ops;

        hsic->base.lane = hsic->base.ops->map(&hsic->base);
        if (IS_ERR(hsic->base.lane)) {
                err = PTR_ERR(hsic->base.lane);
                goto out;
        }

        err = tegra_xusb_hsic_port_parse_dt(hsic);
        if (err < 0) {
                tegra_xusb_port_unregister(&hsic->base);
                goto out;
        }

        list_add_tail(&hsic->base.list, &padctl->ports);

out:
        of_node_put(np);
        return err;
}

void tegra_xusb_hsic_port_release(struct tegra_xusb_port *port)
{
        struct tegra_xusb_hsic_port *hsic = to_hsic_port(port);

        kfree(hsic);
}

static int tegra_xusb_usb3_port_parse_dt(struct tegra_xusb_usb3_port *usb3)
{
        struct tegra_xusb_port *port = &usb3->base;
        struct device_node *np = port->dev.of_node;
        enum usb_device_speed maximum_speed;
        u32 value;
        int err;

        err = of_property_read_u32(np, "nvidia,usb2-companion", &value);
        if (err < 0) {
                dev_err(&port->dev, "failed to read port: %d\n", err);
                return err;
        }

        usb3->port = value;

        usb3->internal = of_property_read_bool(np, "nvidia,internal");

        if (device_property_present(&port->dev, "maximum-speed")) {
                maximum_speed =  usb_get_maximum_speed(&port->dev);
                if (maximum_speed == USB_SPEED_SUPER)
                        usb3->disable_gen2 = true;
                else if (maximum_speed == USB_SPEED_SUPER_PLUS)
                        usb3->disable_gen2 = false;
                else
                        return -EINVAL;
        }

        return 0;
}

static int tegra_xusb_add_usb3_port(struct tegra_xusb_padctl *padctl,
                                    unsigned int index)
{
        struct tegra_xusb_usb3_port *usb3;
        struct device_node *np;
        int err = 0;

        /*
         * If there is no supplemental configuration in the device tree the
         * port is unusable. But it is valid to configure only a single port,
         * hence return 0 instead of an error to allow ports to be optional.
         */
        np = tegra_xusb_find_port_node(padctl, "usb3", index);
        if (!np || !of_device_is_available(np))
                goto out;

        usb3 = kzalloc_obj(*usb3);
        if (!usb3) {
                err = -ENOMEM;
                goto out;
        }

        err = tegra_xusb_port_init(&usb3->base, padctl, np, "usb3", index);
        if (err < 0)
                goto out;

        usb3->base.ops = padctl->soc->ports.usb3.ops;

        usb3->base.lane = usb3->base.ops->map(&usb3->base);
        if (IS_ERR(usb3->base.lane)) {
                err = PTR_ERR(usb3->base.lane);
                goto out;
        }

        err = tegra_xusb_usb3_port_parse_dt(usb3);
        if (err < 0) {
                tegra_xusb_port_unregister(&usb3->base);
                goto out;
        }

        list_add_tail(&usb3->base.list, &padctl->ports);

out:
        of_node_put(np);
        return err;
}

void tegra_xusb_usb3_port_release(struct tegra_xusb_port *port)
{
        struct tegra_xusb_usb3_port *usb3 = to_usb3_port(port);

        kfree(usb3);
}

static void __tegra_xusb_remove_ports(struct tegra_xusb_padctl *padctl)
{
        struct tegra_xusb_port *port, *tmp;

        list_for_each_entry_safe_reverse(port, tmp, &padctl->ports, list) {
                list_del(&port->list);
                tegra_xusb_port_unregister(port);
        }
}

static int tegra_xusb_find_unused_usb3_port(struct tegra_xusb_padctl *padctl)
{
        struct device_node *np;
        unsigned int i;

        for (i = 0; i < padctl->soc->ports.usb3.count; i++) {
                np = tegra_xusb_find_port_node(padctl, "usb3", i);
                if (!np || !of_device_is_available(np))
                        return i;
        }

        return -ENODEV;
}

static bool tegra_xusb_port_is_companion(struct tegra_xusb_usb2_port *usb2)
{
        unsigned int i;
        struct tegra_xusb_usb3_port *usb3;
        struct tegra_xusb_padctl *padctl = usb2->base.padctl;

        for (i = 0; i < padctl->soc->ports.usb3.count; i++) {
                usb3 = tegra_xusb_find_usb3_port(padctl, i);
                if (usb3 && usb3->port == usb2->base.index)
                        return true;
        }

        return false;
}

static int tegra_xusb_update_usb3_fake_port(struct tegra_xusb_usb2_port *usb2)
{
        int fake;

        /* Disable usb3_port_fake usage by default and assign if needed */
        usb2->usb3_port_fake = -1;

        if ((usb2->mode == USB_DR_MODE_OTG ||
             usb2->mode == USB_DR_MODE_PERIPHERAL) &&
                !tegra_xusb_port_is_companion(usb2)) {
                fake = tegra_xusb_find_unused_usb3_port(usb2->base.padctl);
                if (fake < 0) {
                        dev_err(&usb2->base.dev, "no unused USB3 ports available\n");
                        return -ENODEV;
                }

                dev_dbg(&usb2->base.dev, "Found unused usb3 port: %d\n", fake);
                usb2->usb3_port_fake = fake;
        }

        return 0;
}

static int tegra_xusb_setup_ports(struct tegra_xusb_padctl *padctl)
{
        struct tegra_xusb_port *port;
        struct tegra_xusb_usb2_port *usb2;
        unsigned int i;
        int err = 0;

        mutex_lock(&padctl->lock);

        for (i = 0; i < padctl->soc->ports.usb2.count; i++) {
                err = tegra_xusb_add_usb2_port(padctl, i);
                if (err < 0)
                        goto remove_ports;
        }

        for (i = 0; i < padctl->soc->ports.ulpi.count; i++) {
                err = tegra_xusb_add_ulpi_port(padctl, i);
                if (err < 0)
                        goto remove_ports;
        }

        for (i = 0; i < padctl->soc->ports.hsic.count; i++) {
                err = tegra_xusb_add_hsic_port(padctl, i);
                if (err < 0)
                        goto remove_ports;
        }

        for (i = 0; i < padctl->soc->ports.usb3.count; i++) {
                err = tegra_xusb_add_usb3_port(padctl, i);
                if (err < 0)
                        goto remove_ports;
        }

        if (padctl->soc->need_fake_usb3_port) {
                for (i = 0; i < padctl->soc->ports.usb2.count; i++) {
                        usb2 = tegra_xusb_find_usb2_port(padctl, i);
                        if (!usb2)
                                continue;

                        err = tegra_xusb_update_usb3_fake_port(usb2);
                        if (err < 0)
                                goto remove_ports;
                }
        }

        list_for_each_entry(port, &padctl->ports, list) {
                err = port->ops->enable(port);
                if (err < 0)
                        dev_err(padctl->dev, "failed to enable port %s: %d\n",
                                dev_name(&port->dev), err);
        }

        goto unlock;

remove_ports:
        __tegra_xusb_remove_ports(padctl);
unlock:
        mutex_unlock(&padctl->lock);
        return err;
}

static void tegra_xusb_remove_ports(struct tegra_xusb_padctl *padctl)
{
        mutex_lock(&padctl->lock);
        __tegra_xusb_remove_ports(padctl);
        mutex_unlock(&padctl->lock);
}

static int tegra_xusb_padctl_probe(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        const struct tegra_xusb_padctl_soc *soc;
        struct tegra_xusb_padctl *padctl;
        const struct of_device_id *match;
        int err;

        /* for backwards compatibility with old device trees */
        np = of_get_child_by_name(np, "pads");
        if (!np) {
                dev_warn(&pdev->dev, "deprecated DT, using legacy driver\n");
                return tegra_xusb_padctl_legacy_probe(pdev);
        }

        of_node_put(np);

        match = of_match_node(tegra_xusb_padctl_of_match, pdev->dev.of_node);
        soc = match->data;

        padctl = soc->ops->probe(&pdev->dev, soc);
        if (IS_ERR(padctl))
                return PTR_ERR(padctl);

        platform_set_drvdata(pdev, padctl);
        INIT_LIST_HEAD(&padctl->ports);
        INIT_LIST_HEAD(&padctl->lanes);
        INIT_LIST_HEAD(&padctl->pads);
        mutex_init(&padctl->lock);

        padctl->regs = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(padctl->regs)) {
                err = PTR_ERR(padctl->regs);
                goto remove;
        }

        padctl->rst = devm_reset_control_get(&pdev->dev, NULL);
        if (IS_ERR(padctl->rst)) {
                err = PTR_ERR(padctl->rst);
                goto remove;
        }

        padctl->supplies = devm_kcalloc(&pdev->dev, padctl->soc->num_supplies,
                                        sizeof(*padctl->supplies), GFP_KERNEL);
        if (!padctl->supplies) {
                err = -ENOMEM;
                goto remove;
        }

        regulator_bulk_set_supply_names(padctl->supplies,
                                        padctl->soc->supply_names,
                                        padctl->soc->num_supplies);

        err = devm_regulator_bulk_get(&pdev->dev, padctl->soc->num_supplies,
                                      padctl->supplies);
        if (err < 0) {
                dev_err_probe(&pdev->dev, err, "failed to get regulators\n");
                goto remove;
        }

        err = reset_control_deassert(padctl->rst);
        if (err < 0)
                goto remove;

        err = regulator_bulk_enable(padctl->soc->num_supplies,
                                    padctl->supplies);
        if (err < 0) {
                dev_err(&pdev->dev, "failed to enable supplies: %d\n", err);
                goto reset;
        }

        err = tegra_xusb_setup_pads(padctl);
        if (err < 0) {
                dev_err(&pdev->dev, "failed to setup pads: %d\n", err);
                goto power_down;
        }

        err = tegra_xusb_setup_ports(padctl);
        if (err) {
                const char *level = KERN_ERR;

                if (err == -EPROBE_DEFER)
                        level = KERN_DEBUG;

                dev_printk(level, &pdev->dev,
                           dev_fmt("failed to setup XUSB ports: %d\n"), err);
                goto remove_pads;
        }

        return 0;

remove_pads:
        tegra_xusb_remove_pads(padctl);
power_down:
        regulator_bulk_disable(padctl->soc->num_supplies, padctl->supplies);
reset:
        reset_control_assert(padctl->rst);
remove:
        platform_set_drvdata(pdev, NULL);
        soc->ops->remove(padctl);
        return err;
}

static void tegra_xusb_padctl_remove(struct platform_device *pdev)
{
        struct tegra_xusb_padctl *padctl = platform_get_drvdata(pdev);
        int err;

        tegra_xusb_remove_ports(padctl);
        tegra_xusb_remove_pads(padctl);

        err = regulator_bulk_disable(padctl->soc->num_supplies,
                                     padctl->supplies);
        if (err < 0)
                dev_err(&pdev->dev, "failed to disable supplies: %d\n", err);

        err = reset_control_assert(padctl->rst);
        if (err < 0)
                dev_err(&pdev->dev, "failed to assert reset: %d\n", err);

        padctl->soc->ops->remove(padctl);
}

static __maybe_unused int tegra_xusb_padctl_suspend_noirq(struct device *dev)
{
        struct tegra_xusb_padctl *padctl = dev_get_drvdata(dev);

        if (padctl->soc && padctl->soc->ops && padctl->soc->ops->suspend_noirq)
                return padctl->soc->ops->suspend_noirq(padctl);

        return 0;
}

static __maybe_unused int tegra_xusb_padctl_resume_noirq(struct device *dev)
{
        struct tegra_xusb_padctl *padctl = dev_get_drvdata(dev);

        if (padctl->soc && padctl->soc->ops && padctl->soc->ops->resume_noirq)
                return padctl->soc->ops->resume_noirq(padctl);

        return 0;
}

static const struct dev_pm_ops tegra_xusb_padctl_pm_ops = {
        SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_xusb_padctl_suspend_noirq,
                                      tegra_xusb_padctl_resume_noirq)
};

static struct platform_driver tegra_xusb_padctl_driver = {
        .driver = {
                .name = "tegra-xusb-padctl",
                .of_match_table = tegra_xusb_padctl_of_match,
                .pm = &tegra_xusb_padctl_pm_ops,
        },
        .probe = tegra_xusb_padctl_probe,
        .remove = tegra_xusb_padctl_remove,
};
module_platform_driver(tegra_xusb_padctl_driver);

struct tegra_xusb_padctl *tegra_xusb_padctl_get(struct device *dev)
{
        struct tegra_xusb_padctl *padctl;
        struct platform_device *pdev;
        struct device_node *np;

        np = of_parse_phandle(dev->of_node, "nvidia,xusb-padctl", 0);
        if (!np)
                return ERR_PTR(-EINVAL);

        /*
         * This is slightly ugly. A better implementation would be to keep a
         * registry of pad controllers, but since there will almost certainly
         * only ever be one per SoC that would be a little overkill.
         */
        pdev = of_find_device_by_node(np);
        if (!pdev) {
                of_node_put(np);
                return ERR_PTR(-ENODEV);
        }

        of_node_put(np);

        padctl = platform_get_drvdata(pdev);
        if (!padctl) {
                put_device(&pdev->dev);
                return ERR_PTR(-EPROBE_DEFER);
        }

        return padctl;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_get);

void tegra_xusb_padctl_put(struct tegra_xusb_padctl *padctl)
{
        if (padctl)
                put_device(padctl->dev);
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_put);

int tegra_xusb_padctl_usb3_save_context(struct tegra_xusb_padctl *padctl,
                                        unsigned int port)
{
        if (padctl->soc->ops->usb3_save_context)
                return padctl->soc->ops->usb3_save_context(padctl, port);

        return -ENOSYS;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_usb3_save_context);

int tegra_xusb_padctl_hsic_set_idle(struct tegra_xusb_padctl *padctl,
                                    unsigned int port, bool idle)
{
        if (padctl->soc->ops->hsic_set_idle)
                return padctl->soc->ops->hsic_set_idle(padctl, port, idle);

        return -ENOSYS;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_hsic_set_idle);

int tegra_xusb_padctl_enable_phy_sleepwalk(struct tegra_xusb_padctl *padctl, struct phy *phy,
                                           enum usb_device_speed speed)
{
        struct tegra_xusb_lane *lane = phy_get_drvdata(phy);

        if (lane->pad->ops->enable_phy_sleepwalk)
                return lane->pad->ops->enable_phy_sleepwalk(lane, speed);

        return -EOPNOTSUPP;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_enable_phy_sleepwalk);

int tegra_xusb_padctl_disable_phy_sleepwalk(struct tegra_xusb_padctl *padctl, struct phy *phy)
{
        struct tegra_xusb_lane *lane = phy_get_drvdata(phy);

        if (lane->pad->ops->disable_phy_sleepwalk)
                return lane->pad->ops->disable_phy_sleepwalk(lane);

        return -EOPNOTSUPP;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_disable_phy_sleepwalk);

int tegra_xusb_padctl_enable_phy_wake(struct tegra_xusb_padctl *padctl, struct phy *phy)
{
        struct tegra_xusb_lane *lane = phy_get_drvdata(phy);

        if (lane->pad->ops->enable_phy_wake)
                return lane->pad->ops->enable_phy_wake(lane);

        return -EOPNOTSUPP;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_enable_phy_wake);

int tegra_xusb_padctl_disable_phy_wake(struct tegra_xusb_padctl *padctl, struct phy *phy)
{
        struct tegra_xusb_lane *lane = phy_get_drvdata(phy);

        if (lane->pad->ops->disable_phy_wake)
                return lane->pad->ops->disable_phy_wake(lane);

        return -EOPNOTSUPP;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_disable_phy_wake);

bool tegra_xusb_padctl_remote_wake_detected(struct tegra_xusb_padctl *padctl, struct phy *phy)
{
        struct tegra_xusb_lane *lane = phy_get_drvdata(phy);

        if (lane->pad->ops->remote_wake_detected)
                return lane->pad->ops->remote_wake_detected(lane);

        return false;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_remote_wake_detected);

int tegra_xusb_padctl_usb3_set_lfps_detect(struct tegra_xusb_padctl *padctl,
                                           unsigned int port, bool enable)
{
        if (padctl->soc->ops->usb3_set_lfps_detect)
                return padctl->soc->ops->usb3_set_lfps_detect(padctl, port,
                                                              enable);

        return -ENOSYS;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_usb3_set_lfps_detect);

int tegra_xusb_padctl_set_vbus_override(struct tegra_xusb_padctl *padctl,
                                                        bool val)
{
        if (padctl->soc->ops->vbus_override)
                return padctl->soc->ops->vbus_override(padctl, val);

        return -ENOTSUPP;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_set_vbus_override);

int tegra_phy_xusb_utmi_port_reset(struct phy *phy)
{
        struct tegra_xusb_lane *lane = phy_get_drvdata(phy);
        struct tegra_xusb_padctl *padctl = lane->pad->padctl;

        if (padctl->soc->ops->utmi_port_reset)
                return padctl->soc->ops->utmi_port_reset(phy);

        return -ENOTSUPP;
}
EXPORT_SYMBOL_GPL(tegra_phy_xusb_utmi_port_reset);

void tegra_phy_xusb_utmi_pad_power_on(struct phy *phy)
{
        struct tegra_xusb_lane *lane;
        struct tegra_xusb_padctl *padctl;

        if (!phy)
                return;

        lane = phy_get_drvdata(phy);
        padctl = lane->pad->padctl;

        if (padctl->soc->ops->utmi_pad_power_on)
                padctl->soc->ops->utmi_pad_power_on(phy);
}
EXPORT_SYMBOL_GPL(tegra_phy_xusb_utmi_pad_power_on);

void tegra_phy_xusb_utmi_pad_power_down(struct phy *phy)
{
        struct tegra_xusb_lane *lane;
        struct tegra_xusb_padctl *padctl;

        if (!phy)
                return;

        lane = phy_get_drvdata(phy);
        padctl = lane->pad->padctl;

        if (padctl->soc->ops->utmi_pad_power_down)
                padctl->soc->ops->utmi_pad_power_down(phy);
}
EXPORT_SYMBOL_GPL(tegra_phy_xusb_utmi_pad_power_down);

int tegra_xusb_padctl_get_usb3_companion(struct tegra_xusb_padctl *padctl,
                                    unsigned int port)
{
        struct tegra_xusb_usb2_port *usb2;
        struct tegra_xusb_usb3_port *usb3;
        int i;

        usb2 = tegra_xusb_find_usb2_port(padctl, port);
        if (!usb2)
                return -EINVAL;

        for (i = 0; i < padctl->soc->ports.usb3.count; i++) {
                usb3 = tegra_xusb_find_usb3_port(padctl, i);
                if (usb3 && usb3->port == usb2->base.index)
                        return usb3->base.index;
        }

        return -ENODEV;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_get_usb3_companion);

int tegra_xusb_padctl_get_port_number(struct phy *phy)
{
        struct tegra_xusb_lane *lane;

        if (!phy)
                return -ENODEV;

        lane = phy_get_drvdata(phy);

        return lane->index;
}
EXPORT_SYMBOL_GPL(tegra_xusb_padctl_get_port_number);

MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
MODULE_DESCRIPTION("Tegra XUSB Pad Controller driver");
MODULE_LICENSE("GPL v2");